Primary vs secondary active transport

Question 1

Active Transport

Answer 1

Requires energy to move a solute up its concentration gradient.

Question 2

Primary Active Transport

Answer 2

Powered by a direct source of energy such as ATP or light.

Bacteriohodospin uses light energy to GENERATE a transmembrane proton concentration gradient that can be used for ATP formation.

Question 3

Secondary Active Transport

Answer 3

Driven by an ion concentration gradient.

The active uphill transport of one solute is coupled to the downhill transport of the second solute that was concentrated by primary active transport.

The energy released by the downhill movement of Na + powers the uphill transport of glucose.